Method of manufacturing bars from which bolt-blanks are made.



METHOD OF MANUFACTURING BARS FROM WHICH BOLT BLANKS ARE MADE.

APPLICATION FlLED JUNE 15. ms.

1,205,172. Patented Nov. 21, 1916.

ETHAN I. DODDS, OF PITTSBURGH, PENNSYLVANIA, ASSIGNOR TO FLANNERY BOLT COMPANY, OF PITTSBURGH, PENNSYLVANIA.

METHOD OF MANUFACTURING BARS FROM WHICH BOLT-BLANKS ARE MADE.

Specification of Letters Patent.

Patented Nov. 21, 1916.

Application filed June 15, 1915. Serial No. 34,265.

To all whom it may concern:

Be it known that I, ETHAN I. DoDDs, a citizen of the United States, and a resident of Pittsburgh, in the county of Allegheny and State of Pennsylvania, have invented certain new and useful Improvements in Methods of Manufacturing Bars from. Which Bolt-Blanks are Made; and I do hereby declare the following to be a full, clear. and exact description of the invention, such will enable others skilled in the art to which it appertains to make and use the same.

My invention relates to an improvement in method of manufacturing bars from which bolt blanks are made, the object being to simplify the process of manufacturing the bolt blanks whereby the cost of production of the bolts will be reduced'and the output increased.

The invention consists in rolling a bar or slab into substantially T-shape, bending the side members onto the central member without welding the contacting faces, and rolling the bar into cylindrical shape, thus producing a bar composed of an inner and two side members the latter being united to the same end of the central member.

In the accompanying drawing, Figure 1 is a view in cross section of the slab after its preliminary or first rolling; Fig. 2 is a similar view after it has been rolled into cylindrical shape, and Figs. 3 and at are views of a slightly modified form;

In the manufacture of the bar, I take a slab of any approved shape in cross section preferably circular and pass it through rolls which transform it into a central member 5 and two side members 6, the two side members being joined'to the central member at one edge of the latter, so that the bar after this rolling is substantially T-shape in cross section. The central member 5 is rounded at its outer end as at 7 and the outer faces 8 of the two side members 6 are in the arcs of a circle, so that when the side members are folded against the central member, the bar will be cylindrical in shape. The side members are folded against the central member by rolling which also smooths out and straightens the bar, and the latter as thus formed, is provided with two longitudinal slits 9, both of which are open at one edge and closed at the other. These slits are'at opposite sides of the longitudinal center of the bar, and extend inwardly past the transverse center. After the bar has been thus formed, it may be twisted longitudinally from end to end so that the two slits 9 will be in the form of parallel spirals extending from end to end of the bar.

To make bolts from the bar, the latter is reheated and is fed to a machine which upsets the head and cuts off the blank. By twisting the bar from which the bolt blanks are cut, the twist will be constant and uniform from end to end, and consequently uniform in the blanks that are cut from the bar. The upsetting of the heads welds the walls of the slits at the heads but leaves the walls of the slits in the shank disconnected thus permitting the shank to give or yield, and as the floors of the slits are thin they may be ruptured by the vibrations to which the bolts are subjected thus disconnecting the members constituting the shank and rendering the latter still more flexible.

The construction shown in Figs. 3 and 4 is identical with that shown in Figs. 1 and 2 except that the central member 5 is upset at its free edge so as to slightly overlap or overhang the free edges of the side members as clearly shown in Fig. 4c.

Having fully described my invention what I claim as new and desire to secure by Letters-Patent, is

1. The method herein described of making bolt blanks consisting in forming a bar with a central and two side members both the latter being integral with one end of the central member, and then bending the side members against the central member to form a cylindrical bar with two longitudinal slits therein.

2. The method herein described of making bolt blanks consisting in forming a substantially T-shaped bar, bending the side members onto the central member and upsetting the free end of the central member so that it will slightly overhang the free ends of the side members.

In testimony whereof, I have signed this specification in the presence of two subscribing witnesses.

ETHAN I. DODDS. Witnesses:

F. H. ALLIsoN, EDWIN S. RYcE.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, J). G. i 

